OK, let's crack this. We're given 628 and our task is to multiply it by 3. Essentially, we'll be adding 628 to itself 3 times.
Step 1: 0 + 628 = 628
Step 2: 628 + 628 = 1256
Step 3: 1256 + 628 = 1884

So, 628*3 = 1884